mu-Opioid receptor knockout mice display reduced cocaine conditioned place preference but enhanced sensitization of cocaine-induced locomotion.
Brain Res Mol Brain Res. 2004 Feb 5;121(1-2):123-30. doi: 10.1016/j.molbrainres.2003.10.024.
Brain Res Mol Brain Res. 2004.
PMID: 14969743